| // Copyright (c) 2016 The Rouille developers |
| // Licensed under the Apache License, Version 2.0 |
| // <LICENSE-APACHE or |
| // http://www.apache.org/licenses/LICENSE-2.0> or the MIT |
| // license <LICENSE-MIT or http://opensource.org/licenses/MIT>, |
| // at your option. All files in the project carrying such |
| // notice may not be copied, modified, or distributed except |
| // according to those terms. |
| |
| //! Everything in this module is private, but is still publicly accessible from the outside |
| //! because of the `try_or_400!` macro. |
| |
| use std::error::Error; |
| |
| /// This macro assumes that the current function returns a `Response` and takes a `Result`. |
| /// If the expression you pass to the macro is an error, then a 400 response is returned. |
| /// |
| /// # Example |
| /// |
| /// ``` |
| /// # #[macro_use] extern crate rouille; |
| /// # fn main() { |
| /// use rouille::Request; |
| /// use rouille::Response; |
| /// |
| /// fn handle_something(request: &Request) -> Response { |
| /// let data = try_or_400!(post_input!(request, { |
| /// field1: u32, |
| /// field2: String, |
| /// })); |
| /// |
| /// Response::text("hello") |
| /// } |
| /// # } |
| /// ``` |
| #[macro_export] |
| macro_rules! try_or_400 { |
| ($result:expr) => { |
| match $result { |
| Ok(r) => r, |
| Err(err) => { |
| let json = $crate::try_or_400::ErrJson::from_err(&err); |
| return $crate::Response::json(&json).with_status_code(400); |
| } |
| } |
| }; |
| } |
| |
| #[derive(Serialize)] |
| pub struct ErrJson { |
| description: String, |
| cause: Option<Box<ErrJson>>, |
| } |
| |
| impl ErrJson { |
| pub fn from_err<E: ?Sized + Error>(err: &E) -> ErrJson { |
| let cause = err.source().map(ErrJson::from_err).map(Box::new); |
| ErrJson { |
| description: err.to_string(), |
| cause, |
| } |
| } |
| } |